const fs = require('fs')
const path = require('path')
const express = require('express')
const bodyParser = require('body-parser')
const request = require('./util/request')
const packageJSON = require('./package.json')
const exec = require('child_process').exec
const cache = require('./util/apicache').middleware
const { cookieToJson } = require('./util/index')
const fileUpload = require('express-fileupload')
    // version check
exec('npm info NeteaseCloudMusicApi version', (err, stdout, stderr) => {
    if (!err) {
        let version = stdout.trim()
        if (packageJSON.version < version) {
            console.log(
                `最新版本: ${version}, 当前版本: ${packageJSON.version}, 请及时更新`,
            )
        }
    }
})

const app = express()

// CORS & Preflight request
app.use((req, res, next) => {
    if (req.path !== '/' && !req.path.includes('.')) {
        res.set({
            'Access-Control-Allow-Credentials': true,
            'Access-Control-Allow-Origin': req.headers.origin || '*',
            'Access-Control-Allow-Headers': 'X-Requested-With,Content-Type',
            'Access-Control-Allow-Methods': 'PUT,POST,GET,DELETE,OPTIONS',
            'Content-Type': 'application/json; charset=utf-8',
        })
    }
    req.method === 'OPTIONS' ? res.status(204).end() : next()
})

// cookie parser
app.use((req, res, next) => {
    req.cookies = {};
    (req.headers.cookie || '').split(/\s*;\s*/).forEach((pair) => {
        let crack = pair.indexOf('=')
        if (crack < 1 || crack == pair.length - 1) return
        req.cookies[
            decodeURIComponent(pair.slice(0, crack)).trim()
        ] = decodeURIComponent(pair.slice(crack + 1)).trim()
    })
    next()
})

// body parser
app.use(bodyParser.json())
app.use(bodyParser.urlencoded({ extended: false }))

app.use(fileUpload())

// static
app.use(express.static(path.join(__dirname, 'public')))

// cache
app.use(cache('2 minutes', (req, res) => res.statusCode === 200))
    // router
const special = {
    'daily_signin.js': '/daily_signin',
    'fm_trash.js': '/fm_trash',
    'personal_fm.js': '/personal_fm',
}

fs.readdirSync(path.join(__dirname, 'module'))
    .reverse()
    .forEach((file) => {
        if (!file.endsWith('.js')) return
        let route =
            file in special ?
            special[file] :
            '/' + file.replace(/\.js$/i, '').replace(/_/g, '/')
        let question = require(path.join(__dirname, 'module', file))

        app.use(route, (req, res) => {
            if (typeof req.query.cookie === 'string') {
                req.query.cookie = cookieToJson(req.query.cookie)
            }
            let query = Object.assign({}, { cookie: req.cookies },
                req.query,
                req.body,
                req.files,
            )

            question(query, request)
                .then((answer) => {
                    console.log('[OK]', decodeURIComponent(req.originalUrl))
                    res.append('Set-Cookie', answer.cookie)
                    res.status(answer.status).send(answer.body)
                })
                .catch((answer) => {
                    console.log('[ERR]', decodeURIComponent(req.originalUrl), {
                        status: answer.status,
                        body: answer.body,
                    })
                    if (answer.body.code == '301') answer.body.msg = '需要登录'
                    res.append('Set-Cookie', answer.cookie)
                    res.status(answer.status).send(answer.body)
                })
        })
    })

const port = process.env.PORT || 3000
const host = process.env.HOST || ''

app.server = app.listen(port, host, () => {
    console.log(`server running @ http://${host ? host : 'localhost'}:${port}`)
})

module.exports = app